LEWISTON — A research project measuring bacterial levels on bathroom door handles won first place in the Lewiston High School Science Fair, held May 12.

The LHS sophomores whose four projects were judged the best were honored during the high school’s annual Night of Excellence on May 31.

Bates College, a sponsor of the fair, welcomed the four winners for an afternoon visit to the campus that included an opportunity to perform an experiment in a college lab.

Fair organizers for the second year were Andrew Kageleiry, a Bates junior from Dover, N.H., and junior Colby Maldini of New Castle, N.H. Lewiston High science teacher Laurie Haines oversees the fair.

The projects were assessed by judges from Bates and the community. Emily Craft won first place in the fair, in which some 250 LHS sophomores explored a wide variety of research interests.

Wanting to know more about the amount of bacteria on bathroom door handles, Craft compared samples from handles on the insides and outsides of several bathroom doors. Culturing and measuring the bacteria, she found 188 percent more bacteria on the door handles used to exit bathrooms — a science-based reminder of the importance of washing one’s hands at the end of bathroom visits.

In second place was Lex Jimenez, who wondered whether the diameter of a dome affected its strength. Jimenez constructed plywood arches of variable diameters that she used to support a bucket containing sand in increasing amounts until the plywood broke. Jimenez discovered that, in accordance with her hypothesis, the arch with the shortest span supported the most weight.

McKayla Girardin won third place for investigating which age groups thought about sex the most. Categorized by decades, five groups were asked 25 questions with key words that might trigger a sexual response, and their answers were rated on a 100-point scale. Expecting to find that teenagers were the most susceptible, Girardin discovered instead that the 30-39 age group won that distinction. But she concluded that valid data would result only from a sampling that included diverse cultures.

Fourth place went to Jessica Beaulieu, who tested different liquids to determine which ones most effectively prevented apple slices from turning brown. Slices from three different apple varieties were immersed in either water, ginger ale, apple juice or lemon juice, with the last proving most effective because its high acidity counteracts the oxidation that browns the apple’s flesh.